import the original hp sources for the spmath library w/

the a bsd-like hp licensing on 'em.
w/ many thanks to:
Mike Hibler <mike@fast.cs.utah.edu>
James Loveluck <loveluck@ri.silicomp.fr>
Patrick Roudaud <patrick@enserg.fr>

1 files changed, 196 insertions, 0 deletions

diff --git a/sys/arch/hppa/spmath/dfsqrt.c b/sys/arch/hppa/spmath/dfsqrt.c
new file mode 100644
index 00000000000..918e1024ec0
--- /dev/null
+++ b/sys/arch/hppa/spmath/dfsqrt.c
@@ -0,0 +1,196 @@
+/*
+ * Copyright 1996 1995 by Open Software Foundation, Inc.   
+ *              All Rights Reserved 
+ *  
+ * Permission to use, copy, modify, and distribute this software and 
+ * its documentation for any purpose and without fee is hereby granted, 
+ * provided that the above copyright notice appears in all copies and 
+ * that both the copyright notice and this permission notice appear in 
+ * supporting documentation. 
+ *  
+ * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
+ * FOR A PARTICULAR PURPOSE. 
+ *  
+ * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 
+ * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 
+ * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 
+ * 
+ */
+/*
+ * pmk1.1
+ */
+/*
+ * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
+ *
+ * To anyone who acknowledges that this file is provided "AS IS" 
+ * without any express or implied warranty:
+ *     permission to use, copy, modify, and distribute this file 
+ * for any purpose is hereby granted without fee, provided that 
+ * the above copyright notice and this notice appears in all 
+ * copies, and that the name of Hewlett-Packard Company not be 
+ * used in advertising or publicity pertaining to distribution 
+ * of the software without specific, written prior permission.  
+ * Hewlett-Packard Company makes no representations about the 
+ * suitability of this software for any purpose.
+ */
+/* $Source: /cvs/OpenBSD/src/sys/arch/hppa/spmath/dfsqrt.c,v $
+ * $Revision: 1.1 $	$Author: mickey $
+ * $State: Exp $   	$Locker:  $
+ * $Date: 1998/06/23 20:33:54 $
+ */
+
+#include "../spmath/float.h"
+#include "../spmath/dbl_float.h"
+
+/*
+ *  Double Floating-point Square Root
+ */
+
+/*ARGSUSED*/
+dbl_fsqrt(srcptr,nullptr,dstptr,status)
+
+dbl_floating_point *srcptr, *dstptr;
+unsigned int *nullptr, *status;
+{
+	register unsigned int srcp1, srcp2, resultp1, resultp2;
+	register unsigned int newbitp1, newbitp2, sump1, sump2;
+	register int src_exponent;
+	register boolean guardbit = FALSE, even_exponent;
+
+	Dbl_copyfromptr(srcptr,srcp1,srcp2);
+        /*
+         * check source operand for NaN or infinity
+         */
+        if ((src_exponent = Dbl_exponent(srcp1)) == DBL_INFINITY_EXPONENT) {
+                /*
+                 * is signaling NaN?
+                 */
+                if (Dbl_isone_signaling(srcp1)) {
+                        /* trap if INVALIDTRAP enabled */
+                        if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+                        /* make NaN quiet */
+                        Set_invalidflag();
+                        Dbl_set_quiet(srcp1);
+                }
+                /*
+                 * Return quiet NaN or positive infinity.
+		 *  Fall thru to negative test if negative infinity.
+                 */
+		if (Dbl_iszero_sign(srcp1) || 
+		    Dbl_isnotzero_mantissa(srcp1,srcp2)) {
+                	Dbl_copytoptr(srcp1,srcp2,dstptr);
+                	return(NOEXCEPTION);
+		}
+        }
+
+        /*
+         * check for zero source operand
+         */
+	if (Dbl_iszero_exponentmantissa(srcp1,srcp2)) {
+		Dbl_copytoptr(srcp1,srcp2,dstptr);
+		return(NOEXCEPTION);
+	}
+
+        /*
+         * check for negative source operand 
+         */
+	if (Dbl_isone_sign(srcp1)) {
+		/* trap if INVALIDTRAP enabled */
+		if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
+		/* make NaN quiet */
+		Set_invalidflag();
+		Dbl_makequietnan(srcp1,srcp2);
+		Dbl_copytoptr(srcp1,srcp2,dstptr);
+		return(NOEXCEPTION);
+	}
+
+	/*
+	 * Generate result
+	 */
+	if (src_exponent > 0) {
+		even_exponent = Dbl_hidden(srcp1);
+		Dbl_clear_signexponent_set_hidden(srcp1);
+	}
+	else {
+		/* normalize operand */
+		Dbl_clear_signexponent(srcp1);
+		src_exponent++;
+		Dbl_normalize(srcp1,srcp2,src_exponent);
+		even_exponent = src_exponent & 1;
+	}
+	if (even_exponent) {
+		/* exponent is even */
+		/* Add comment here.  Explain why odd exponent needs correction */
+		Dbl_leftshiftby1(srcp1,srcp2);
+	}
+	/*
+	 * Add comment here.  Explain following algorithm.
+	 * 
+	 * Trust me, it works.
+	 *
+	 */
+	Dbl_setzero(resultp1,resultp2);
+	Dbl_allp1(newbitp1) = 1 << (DBL_P - 32);
+	Dbl_setzero_mantissap2(newbitp2);
+	while (Dbl_isnotzero(newbitp1,newbitp2) && Dbl_isnotzero(srcp1,srcp2)) {
+		Dbl_addition(resultp1,resultp2,newbitp1,newbitp2,sump1,sump2);
+		if(Dbl_isnotgreaterthan(sump1,sump2,srcp1,srcp2)) {
+			Dbl_leftshiftby1(newbitp1,newbitp2);
+			/* update result */
+			Dbl_addition(resultp1,resultp2,newbitp1,newbitp2,
+			 resultp1,resultp2);  
+			Dbl_subtract(srcp1,srcp2,sump1,sump2,srcp1,srcp2);
+			Dbl_rightshiftby2(newbitp1,newbitp2);
+		}
+		else {
+			Dbl_rightshiftby1(newbitp1,newbitp2);
+		}
+		Dbl_leftshiftby1(srcp1,srcp2);
+	}
+	/* correct exponent for pre-shift */
+	if (even_exponent) {
+		Dbl_rightshiftby1(resultp1,resultp2);
+	}
+
+	/* check for inexact */
+	if (Dbl_isnotzero(srcp1,srcp2)) {
+		if (!even_exponent & Dbl_islessthan(resultp1,resultp2,srcp1,srcp2)) {
+			Dbl_increment(resultp1,resultp2);
+		}
+		guardbit = Dbl_lowmantissap2(resultp2);
+		Dbl_rightshiftby1(resultp1,resultp2);
+
+		/*  now round result  */
+		switch (Rounding_mode()) {
+		case ROUNDPLUS:
+		     Dbl_increment(resultp1,resultp2);
+		     break;
+		case ROUNDNEAREST:
+		     /* stickybit is always true, so guardbit 
+		      * is enough to determine rounding */
+		     if (guardbit) {
+			    Dbl_increment(resultp1,resultp2);
+		     }
+		     break;
+		}
+		/* increment result exponent by 1 if mantissa overflowed */
+		if (Dbl_isone_hiddenoverflow(resultp1)) src_exponent+=2;
+
+		if (Is_inexacttrap_enabled()) {
+			Dbl_set_exponent(resultp1,
+			 ((src_exponent-DBL_BIAS)>>1)+DBL_BIAS);
+			Dbl_copytoptr(resultp1,resultp2,dstptr);
+			return(INEXACTEXCEPTION);
+		}
+		else Set_inexactflag();
+	}
+	else {
+		Dbl_rightshiftby1(resultp1,resultp2);
+	}
+	Dbl_set_exponent(resultp1,((src_exponent-DBL_BIAS)>>1)+DBL_BIAS);
+	Dbl_copytoptr(resultp1,resultp2,dstptr);
+	return(NOEXCEPTION);
+}